Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [308]-338).

An algebraic variety is called rationally connected if two generic points can be connected by a curve isomorphic to the projective line. The output of the minimal model program applied to rationally connected variety is variety admitting Mori fiber spaces over a rationally connected base. In this thesis we study the birational geometry of a particular class of rationally connected Mori fiber spaces: Fano fibrations over the projective line. We construct examples of Fano fibrations with a unique Mori fiber space in their birational classes. We prove that these examples are not birational to varieties of Fano type, thus answering the question of Cascini and Gongyo. That is we prove that the classes of rationally connected varieties and varieties of Fano type are not birationally equivalent. To construct the examples we use the techniques of birational rigidity. A Mori fiber space is called birationally rigid if there is a unique Mori fiber space structure in its birational class. The birational rigidity of smooth varieties admitting a del Pezzo fibration of degrees 1 and 2 is a well studied question. Unfortunately it is not enough to study smooth del Pezzo fibrations as there are fibrations which do not have smooth or even smoothable minimal models. In the case of fibrations of degree 2 we know that there is a minimal model with 2-Gorenstein singularities. These singularities are degenerations of the simplest terminal quotient singularity: singular points of the type 1/2(1,1,1). We give first examples of birationally rigid del Pezzo fibrations with 2-Gorenstein singularities. We then apply this result to study finite subgroups of the Cremona group of rank three. We then study the birational geometry of Fano fibrations from a different side. Using the reduction to characteristic 2 method we prove that double covers of Pn-bundles over Pm branched over a divisor of sufficiently high degree are not stably rational. For a del Pezzo fibration Y→P1 of degree 2 such that X is smooth there is a double cover Y→ X, where X is a P2-bundle over P1. In this case a stronger result holds: a very general Y with Pic(Y)≅Z⊕Z is not stably rational. We discuss the proof of this statement.

Transgenesis of silkworms has great potential for the development of silk with new properties as well as for the preparation of recombinant proteins for the use in biomedicine. Zabelina et al. (2015a) showed that transgenesis of parthenogenetic silkworms facilitates the selection and maintenance of transgenic homozygotes with stabile transgene insertions. However, the efficiency of transgenesis was less than 2 % compared to 60 % in the standard, non-parthenogenetic silkworms. The purpose of the present research was to explore the cause of this difference. Since transgenesis is normally performed at 25 °C but in the parthenogenetic silkworms at 15 °C (3 days incubation at this temperature is part of the protocol for the induction of parthenogenetic development), we assumed that the eggs incubated at 15 °C might have been injected with the DNA construct at unsuitable time. The work was therefore focused on the rate of embryogenesis at 15 °C in the eggs treated in different ways. Intensive cleavage of the control eggs (strain K23) was observed at 12 h after oviposition at 25 °C and between 24 and 36 h at 15 °C. The transgenesis of parthenogenetic silkworms is also complicated by the embryonic diapause. In the current work, diapause was suppressed by implanting PK1 ovaries into the non-parthenogenetic male hosts K23. Parthenogenetic development was activated by the heat shock in the chorionated eggs dissected from the implants. No cleavage was detected at 12 h after the acti-vation and nearly complete blastoderm was found at 48 h. In respect to the course of cleavage at 15 °C, transgene injection 24 h after the activating heat shock can be recommended. The eggs from endogenous ovaries of the K23 females, which also contained the implants of the PK1 ovaries, acquired partial capacity of parthenogenesis. Low rate of embryogenesis was also found in the transgenic clone VTG1. Current results suggest that more research is needed to understand and possibly explore differences in the rate of silkworms exposed to different treatments.

The spun-out silk fiber consists of two fibroin filaments that are cemented together by sericin coating. The serine-rich sericins, which make 20-30% of the cocoon silk proteins in Bombyx mori, are dissolved in hot water during silk fiber reeling from the cocoon. The sericin extract is usually discarded. Only small amounts are currently used in cosmetics and lately also as replacement of bovine serum products in the cell culture media. The use in culture media is hindered by poor standardization of the extracts. To overcome this problem, we attempted preparation of several recombinant proteins based on partial sequences of one out of the three sericin genes of Bombyx mori, sericin 3. Translation product of the Ser3 gene is extremely serine-rich with a relatively high representation of the aspartate, asparagin, glutamate, and glutamine. Using specific primers we have prepared a cDNAs of 267, 279, 525, 672, and 528 bp, respectively, derived from the Ser3 gene. The cDNAs were cloned and expressed as fusion proteins with hexahistidine in Escherichia coli. The proteins were purified by affinity chromatography and analyzed by acrylamide electrophoresis. Ser3 gene contain repetitive motifs rich in serine and including some charged amino acids.

Le manuscrit de thèse se propose de concilier les points de vue développés par les théories microscopiques et la théorie hydrodynamique sur la diffusion. Nous testons les hypothèses hydrodynamiques et tentons d'obtenir une reformulation de celles-ci à partir d'arguments microscopiques. En particulier, pour un fluide laminaire visqueux, la force exercée sur une particule sphérique ou encore le champ de vitesse autour d'une particule sphérique en mouvement, respectivement décrits par la force de Basset-Boussinesq et la solution de Stokes, seront l'objet de notre investigation. Leurs formes sont-elles pertinentes à l'échelle microscopique ? Si oui, comment peut-on les exprimer à l'échelle moléculaire ? Pour ce faire, nous avons réalisé des simulations moléculaires et basé notre développement à l'aide de la théorie de Mori-Zwanzig. Dans un premier temps, nous étudions l'évolution des fluctuations de la particule afin d'interpréter le comportement aux temps longs et réalisons le lien avec l'inertie, la diffusion et l'hydrodynamique. Puis nous proposons une nouvelle approche pour extraire le flot microscopique de fluides Lennard-Jones ou granulaires afin de le comparer directement aux solutions hydrodynamiques, ce qui nous permet d'étudier les conditions aux bords. Nous avons pu développer une expression analytique pour les conditions aux bords du flot où les fluctuations jouent un rôle clef. A l'aide des outils d'analyse développés, nous pouvons aussi investiguer le couplage entre le mouvement translationnel et rotationnel. Enfin nous étendons notre analyse à des systèmes tels que les ions aqueux et l'eau surfondue. / This work proposes to reconcile the points of view developed by microscopic theories and hydrodynamics on diffusion. We test the hydrodynamics hypothesis and try reformulate them from microscopic arguments. In particular, for a laminar viscous liquid, the exerced force on a spherical particle or the velocity field around the spherical particle with a prescribed velocity, respectively described by the Basset-Boussinesq force and the Stokes flow, will be the object of our investigation. Is their form relevant at microscopic scale ? If so, how can we express them at the molecular scale ? To do so, we realized molecular simulations and based our developement thanks to the Mori-Zwanzig theory which gives us exact microscopic relations. Initally, we study the evolution of fluctuations of the particle in order to interpret the behaviour at long times and link it with inertia, diffusion and hydrodynamics. Then we propose a novel approch to extract the microscopic flow of Lennard-Jones or granular fluids in order to compare it directly with the hydrodynamic solutions, which allows us to study boundary conditions. We were able to develop an analytical expression for boundary conditions of the flow where fluctuations play a key role. Thanks to our developed analysis tools, we also investigate the coupling between the translational and rotational movement. Finally, we extend our investigation to more realistic fluids such as aqueous solutions and water.

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This diploma thesis is focused on the silk production of invertebrates. The aim of the work is to systematically introduce important species and describe the purpose of their silk production. The ability to produce silk is widespread in many insect families. The production of proteinaceous fibers also occurs in arachnids and (in the form of byssus threads) also in mollusks. The Domestic Silk Moth (Bombyx mori) is an economically important insect, being a primary producer of silk. Hence, an integral part of the thesis focuses on Domestic Silk Moth. In this thesis all developmental stages of Silk Moth (from an egg to an adult) are described. In the past, efforts to breed silkworms also appeared in the Czech lands. Therefore, a short chapter of the thesis is devoted to the history of sericulture. Furthermore, this thesis describes methods of rearing silkworm larvae. For students of Natural Sciences and Biology, it is crucial to be in touch with live objects. Because the silkworm rearing is quite simple, it is possible to incorporate this topic to the school projects about holometabolous insects. The practical part of this thesis contains schedule of practical exercise about silk moths. And in final section of practical part, worksheets for lower-secondary students are presented. Keywords: silkworm...

My degree project has been developed through my research on the topics of originality, consumption, vanitas and consumer culture. It referneces the politics of consumption, desire, pollution, waste, the passing of time, the effect of decay, and death. The scene is a reconstruction of a "still life" scene, referencing Baroque painting. The light-box installation comprises coloured sculptures which are emblems of consumerism. The hanmade and the organic are joined in composition, as if united in ruin and decay. The sculptures resemble the still life genre and allude to memento-mori. The project also addresses the industrial food system. It emphasises efficiency, profit and power in ways that are narrowly constructed, sometimes at the expense of other environmental and social values. It consist of a glass-cast modern cornucopia. The glass captures decomposing traces and makes them solid and everlasting. Even with something so fragile and temporary as life, the material can freeze it in time. The glass captures life.

The goal of this paper is to create a positive account of Masahiro Mori’s theory of the uncanny valley. A theory wherein Mori speculated on the relationship between one’s perceived affinity for a robot and the human-likeness of that same robot. Mori believed that the closer to a human a robot looked, the higher one’s affinity for it would be, until a certain point where the robot looked close enough to a human without being fully convincing. When this happened one would feel a negative affinity for the robot. Mori called this phenomenon the uncanny valley.  In later years, Mori’s theory has gained more popularity and is now applied outside of robotics. Most notably it is often applied to the medium of 3D animation and CGI, which is what this essay will be discussing when trying to create a positive account of the uncanny valley. To do so it will discuss the phenomenon in relation to some examples of 3D animation and CGI that critics have claimed reside in the uncanny valley. This essay will give an overview of what the uncanny valley actually entails as well as give an explanation of how the uncanny valley can be applied to 3D animation.  In order to create a positive account, this essay will claim that the positive aesthetic value that the uncanny valley can lead to is akin to that of Brecht’s idea of the distancing effect. This essay argues that the uncanny valley distances the viewer from what they are viewing and that makes the viewer gain didactic knowledge of both CGI and their own relationship to technology. This essay will argue that this is a positive aesthetic experience that is unique to the uncanny valley.